In the past, there have been attempts to produce smoking articles that provide aerosol or vapors for inhalation rather than conventional smoke. For example, there are smoking articles which have a charcoal rod with a separate carrier impregnated with flavorants and a synthetic "smoke" forming agent. The charcoal rod is coated with a concentrated sugar solution that forms an impervious layer during burning. The coating layer is intended to contain the gases formed during smoking and concentrate the heat the rod generates.
Another example are smoking articles which burn tobacco, as in a conventional cigarette, to heat a metallic cylinder. The metal cylinder contains a source of nicotine (such as reconstituted tobacco or tobacco extract). During smoking, the material inside the metal cylinder releases vapors that mix with air inhaled through an open end of the associated tube. This tube extends to the burning end of the smoking article. Smoking articles similar to the one just described include a tube which becomes frangible upon heating so that it will break off and not protrude as the surrounding tobacco burns.
Yet another example is smoking articles that produce a nicotine-containing aerosol by heating a flavor generator. Hot gases which result from the combustion of a fuel rod or other carbonaceous material heat the flavor generator. A variation of these smoking articles uses a short fuel element. The performance of these smoking articles is improved by maximizing heat transfer between the fuel element and the aerosol generator. A spun glass fiber insulator provides insulation to the fuel element and aerosol generator assembly. Heat transfer is effected by a metallic conductor between the fuel element and flavor generator to conduct heat, and by using the insulation to minimize heat loss.
The smoking articles containing the spun glass fiber insulator have several drawbacks. First, the resilient glass fiber insulating jacket is difficult to handle on modern mass production machinery. Second, the glass fibers may become dislodged during shipping and migrate through the pack to rest on the mouth end of the articles which gives rise to potential inhalation of glass fibers by the smoker. Third, the metallic heat conductor may itself absorb much of the heat produced by the fuel element and not transfer it as required.
The present invention overcomes the problems associated with prior smoking articles that produce no visible sidestream smoke. Moveover, the smoking articles in the prior art do not have the features of the smoking article of the present invention, such as a smoking article that includes an active element and reusable body, with the reusable body having means to eject therefrom at least the heat source and tobacco flavor producing elements of the active element.